An Insider’s View on How
to Become
Level 1 PCI Compliant
(Part 3 of 3)
By: Mitchell H. Levine, CISA
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Audit Serve, Inc.
Audit Serve Seminars
Hidden Secrets from IT
Auditors
Harrisburg, PA - November
20 - 21, 2008 * Pittsburgh, PA January 12, 2009 *
Phoenix, AZ September 14 - 15, 2009
This is the third part of a three part
article intended to provide insights on how to navigate through the PCI
project components.
The PCI project is a costly undertaking
for most organizations because it requires changes to an organization's
system architecture and requires significant changes to the PCI inscope
applications. Unlike other standards, an organization needs to pass all
300+ testing requirements defined in the PCI standards in order to
receive their PCI certification.
Many organizations have designed their
applications in which users connect via Telnet which is not allowed
within PCI because passwords are sent over the network in clear text.
Organizations are forced to implement a SSH (Secure Shell) client
instead which provides a secure encrypted communication between the
Server and the user workstations.
The rollout of SSH is huge since all
users which connect to inscope PCI applications needs to have the
software loaded on their desktop along with the servers which host the
inscope PCI application. In addition, any host-to-host communications
which involve inscope PCI applications would require all connecting
hosts to have the SSH client loaded. In addition, there maybe automated
scripts executed in which connections occurs via telnet which would
require the scripts to be rewritten to conform to the syntax used by the
SSH software used.
Since Telnet would then be turned off on
the PCI inscope servers, any user which does not connect via the SSH
client will not be able to access the system. In addition, the
communication interchange with the newly deployed SSH client needs to be
thoroughly tested to ensure that all messages are received by the user
and they are able to perform all critical functions using the SSH
client. One of the common problems with the deployment of the SSH
clients is the ability for users to receive messages that their
passwords have expired and being able to change their passwords based on
the newly deployed communication interchange.
The encryption of data at rest and while it is in transit are the most
significant, difficult and time consuming requirements within PCI.
Organizations need to perform an end-to-end analysis of the data flow of
their PCI inscope data components to identify each system in which the
PCI inscope data passes and the amount of time in which data is stored.
A case could be made with PCI QSA (Qualified
Security Assessors)
that if data is stored for a few
hours and there are automated processes to delete the PCI inscope data,
then the data does not need to be encrypted at rest.
It is important to understand the
difference in PCI requirements between data which is transported and
data which is stored. Within an organization's internal network there is
not a requirement to encrypt the transmission using wither Transport
Layer Security (TLS) or its predecessor, Secure Sockets Layer (SSL).
This requirement is needed if an organization does not properly segment
their network environment and for data interchanges with external
organizations. If FTP is used, the PCI transmission requirements
applies when an external organizations push data to the PCI
organization’s FTP server and when a PCI organization allows and
external organization to fetch files from its FTP server.
Encrypting data at rest requires an
analysis of the various alternatives for encrypting data. OS level
encryption is not a practical alternative based on the design of most
applications and databases. Therefore, most organizations are deploying
encryption at the database level which is offered by most database
vendors. Database vendors offer the encryption of the entire database
or at the field level. However, besides the performance impact and
storage requirements for deploying encryption at the database level,
there are significant number of application changes which need to be
made to encrypt and decrypt the data. When database encryption is
deployed, the ability to perform adhoc queries will be prevented since
PCI does not allow the distribution of private keys to individual users
to decrypt data.
An alternative to database level
encryption is to deploy the database server on a separate SAN which has
an encryption device sitting between the application server and the
database server.
The last PCI component in which there are
unpublished alternatives for achieving PCI compliance is the need to
have all external parties which handle an organization’s cardholder data
to also become PCI compliant. Since every organization is not willing
to invest in a project to become PCI certified by a QSA, depending on
the volume of credit card data the vendor handles, they could self
certify themselves as a Level 4 vendor. This would only require a
Network Vulnerability scan to be run by a qualified vendor or an
organization which uses a scanning tool which is PCI compliant.
________________ _________________________________________________________
Mitchell Levine is the founder of Audit
Serve, Inc. Audit Serve performs PCI Assessment and Remediation Project
Management consulting services. Audit Serve also conducts Integrated &
IT Audits, SOX Control Design & Testing. Email Mr. Levine at
Levinemh@auditserve.com if you would
like to discuss your organization's specific project requirements in
order to establish a proposal of services.
Copyright 2008, Audit Serve, Inc. All rights reserved.
Reproduction, which includes links from other Web sites, is prohibited except by
permission in writing.
This article appeared in a past issue of the Audit Vision
E-Mail Newsletter.
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